diff --git a/test/cabal.project b/test/cabal.project
new file mode 100644
index 0000000..9f0c53f
--- /dev/null
+++ b/test/cabal.project
@@ -0,0 +1,15 @@
+packages:
+  optics/*.cabal
+  optics-core/*.cabal
+  optics-extra/*.cabal
+  optics-sop/*.cabal
+  optics-th/*.cabal
+  optics-vl/*.cabal
+  indexed-profunctors/*.cabal
+  template-haskell-optics/*.cabal
+
+-- An example, using optics to generate optics diagrams
+packages:
+  metametapost/*.cabal
+
+tests: true